Nature and extent of the burden and risks associated with participation, benefit and group relatedness: The risks related to the conduct of this study are negligible and the burden minimal. Patients in both groups receive the current standard of care. Patients randomized in the capnography group could get benefit from the addition of capnography to the monitoring by early detection of alveolar hypoventilation. Capnography is a noninvasive measurement by means of a cannula under the nose, which before the sedation may tickle, but during sedation no inconvenience is expected.